#define _CRT_SECURE_NO_WARNINGS 1
#include<iostream>
#include<string>

using namespace std;

class Solution {
public:
    bool isPalindrome(string s) {
        string a;
        for (auto x : s)
        {
            if (x >= 'a' && x <= 'z')
            {
                a += x;
            }
            else if (x >= 'A' && x <= 'Z')
            {
                a += x + 32;
            }
            else if (x >= '0' && x <= '9')
            {
                a += x;
            }
        }

        int end = a.size() - 1;
        int begin = 0;


        while (begin <= end)
        {
            if (a[begin++] != a[end--])
            {
                return false;
            }
        }
        return true;
    }
};

int main()
{
    Solution solution;
    return 0;
}